Coil winding form



D. c. SPITZ 3,141,632

July 21, 1964 COIL WINDING FORM Filed Feb. 13, 1962 IN V EN TOR.

D aniel C- EJPi cZ BY United States Patent 3,141,632 CUIL WINDING FORM Daniel (I. Spitz, Springfield, Va, assignor to the United States of America as represented by the ecretary oi the Army Filed Feb. I3, 1952, Ser. No. 173,078 2 (Ilaims. (Cl. 242-118.6) (Granted under Titie 35, US. Code (1952-), see. 2&6)

The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to coil winding forms and more particularly to a process for winding coil which utilizes a form made of a material having the ability to withstand heat and the further ability of not adhering to impregnants.

A material having such qualities is Teflon, which is defined as follows in Bennet, Chemical and Technical Dictionary (Chemical Publishing (30., 1947): Polymerizcd tetrafluoro ethylene; a synthetic plastic.

In the present invention a coil of wire is wound on a form made of a material, such as Teflon, and remains on the form during impregnation with varnishes or other impregnants and also during baking. After the foregoing treatment has molded the coil into a rigid structure, the form may be removed. As is the practice, paper may be used for the purpose of providing electrical insulation and will not appreciably increase the size of the coil.

Prior to this invention, it was necessary to construct a bobbin of paper, Bakelite, or some other insulating material having suflicient mechanical strength to hold the coil to its required shape during the winding, impregnating and baking process. The bobbin structure was therefore, in many cases, much heavier and more bulky than would be required for electrical insulation.

It is an object of this invention to provide a coil form incorporating Teflon material in such a way as to enable the wound coil to be impregnated, baked and subsequent-- 1y easily removed from the form.

It is another object of this invention to enable coils to be wound and impregnated Without the use of bobbins of insulating material which become a permanent part of the completed coil structure.

It is a further object of this invention to provide a form for winding coils of various sizes.

It is also an object of this invention to make it possible to wind a greater number of turns of the same kind of Wire in a given space than formerly.

The invention will be better understood and described by reference to the accompanying drawings which form a part of this application and in which:

FIGURE 1 is a view illustrating an assembled coil winding form;

FIGURE 2 is an exploded view of the coil winding form;

FIGURE 3 is a cross section of the axle taken along line 3-3 of FIGURE 2;

FIGURE 4- is a cross sectional view of an alternate type axle; and

FIGURE 5 is a view indicating the use of an optional spindle form.

Referring to FIGURE 2, there is shown an axle 11 having a cross sectional form as shown in FIGURE 3 3,lll,632 Patented July 21, I964 ice or in modified form as in FIGURE 4. Centrally located upon the axle is a Teflon spindle 12 having a cross sectional area of any desired form. The ends of the spindle may be provided with bosses as at 13, which are of cooperating size with slots I4, 15 in Teflon flanges 16 and 17. As seen in the assembled drawing, the Teflon flanges are snugly positioned on the axle Ill next to the spindle. Disc-shaped face plates 18 and 19, provided with axial longitudinal bores 26 and 21 of cooperating diameter with the axle 11, are positioned next to the flanges 16 and 17. In the face plate surfaces 22 and 23 abutting the flanges a rectangular groove 24 is provided, the width of the groove being substantially equal in dimensions of the previously described boss I3. The face plates 18 and 19 are also provided with a radial hole from the periphery thereof to the longitudinal bore 29 for the purpose of receiving a set screw 25, Which may be of the cup shaped socket head type shown.

There are alternate methods of construction which might be used to make an equivalent coil winding form. For example the parts of the form described as made of Teflon could be made of metal and provided with a Teflon coating. The axle might be of the type having a cross section shown in FIGURE 4, which would eliminate the need for bosses on the spindle because the axle would be more easily removed from it. Materials other than Teflon might be used provided they have the ability to withstand heat and provided they have the property of not adhereing to varnish or other impregnant.

In operation a spindle is made of Teflon or other suitable material and an axle inserted therein. Ends for the spindle are provided in the form of flanges made of Teflon, which results in an assembly as seen in FIGURE 1, in which wire can be wound around the cup shaped center portion and not touch any surface of the device except the Teflon or other suitable material used. The use of Teflon in this manner so that no other material, unless it is equivalent, comes in contact with the coil and impregnant is the heart of this invention. It makes possible impregnation of the coil with varnishes or other impregnants, and baking while still on the form. After these operations have been performed the coil acquires a rigid structure and then it may be easily removed from the spindle. Ease in removing the coil from the spindle is afforded because of the assembly as best seen in FIG- URE 5 which permits the face plates and axle to be removed. The assembly may be reused after a coil is baked on it, simply by removing the completed coil.

While the instant invention has been shown and de scribed herein in a most practical embodiment, it is recognized that departure may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein but is to be awarded the full scope of the claims so as to embrace any and all equivalent apparatus.

I claim:

1. A coil winding form comprising, in combination, an axle; a spindle having a substantially rectangular boss integral with each end thereof and being in axial alignment with each other, said spindle being centrally disposed on said axle; a pair of flanges, each flange having a central slot conforming to the contour of said bosses, each of said flanges being fitted on each of said bosses and in abutting relation to said spindle; a pair of discshaped plates, each having an axial bore therethrough ar d References Cites i the file of this patent a diametrical, rectangular groove in its inner face, said UNITED STATES PATENTS groove being of a Width substantially the same as the Width of said bosses, said plates being fitted on aid axle 2,946,996 July g6, 1262 whereby said groove receives a portion of a said boss 5 3:036J92 Rfiem 3 and each of said plates will abut a said flange; and a set OTHER REFERENCES screw in each said disc for securing said discs against axial movement along said axle to maintain said winding Du Pol-1t Produst Engineering 13111165111 Teflon Demonf i i bl d condition strates Its Versatile Properties as an Engineering Mate- 2. A coil Winding form as set forth in claim 1 where- 10 T1311 11! These ppi 1955- in said spindle and said flanges are formed of Teflon. Du Pom Bulleimi Teflon, August 1957- 

1. A COIL WINDING FORM COMPRISING, IN COMBINATION, AN AXLE; A SPINDLE HAVING A SUBSTANTIALLY RECTANGULAR BOSS INTEGRAL WITH EACH END THEREOF AND BEING IN AXIAL ALIGNMENT WITH EACH OTHER, SAID SPINDLE BEING CENTRALLY DISPOSED ON SAID AXLE; A PAIR OF FLANGES, EACH FLANGE HAVING A CENTRAL SLOT CONFORMING TO THE CONTOUR OF SAID BOSSES, EACH OF SAID FLANGES BEING FITTED ON EACH OF SAID BOSSES AND IN ABUTTING RELATION TO SAID SPINDLE; A PAIR OF DISCSHAPED PLATES, EACH HAVING AN AXIAL BORE THERETHROUGH AND A DIAMETRICAL, RECTANGULAR GROOVE IN ITS INNER FACE, SAID GROOVE BEING OF A WIDTH SUBSTANTIALLY THE SAME AS THE WIDTH OF SAID BOSSES, SAID PLATES BEING FITTED ON SAID AXLE WHEREBY SAID GROOVE RECEIVES A PORTION OF A SAID BOSS AND EACH OF SAID PLATES WILL ABUT A SAID FLANGE; AND A SET SCREW IN EACH SAID DISC FOR SECURING SAID DISCS AGAINST AXIAL MOVEMENT ALONG SAID AXLE TO MAINTAIN SAID WINDING FORM IN ITS ASSEMBLED CONDITION. 